Shock wave catheter with shock absorber

Abstract

A shock wave catheter includes an elongate member and a shock wave emitter assembly located at a distal region of the elongate member. The shock wave emitter assembly includes a shock absorber made of a low durometer material. A shock wave catheter system includes a shock wave catheter with a shock absorber and a high voltage power supply configured to generate high voltage pulses. A method for treating a lesion in a body lumen includes generating shock waves with a shock wave catheter system that includes a shock wave catheter with a shock absorber.

The invention claimed is: 
     
         1 . A catheter for treating lesions in a body lumen, the catheter comprising:
 an elongate member;   at least one shock wave emitter assembly mounted over a distal portion of the elongate member, the at least one shock wave emitter assembly comprising
 an electrode pair comprising:
 an inner electrode; and 
 an outer electrode, the at least one shock wave emitter assembly configured to generate a shock wave when a voltage of no less than 10 kV is applied across the electrode pair; and 
 
 a shock absorber located at least partially between the inner electrode and the outer electrode and surrounding the inner electrode and having an aperture aligned with the inner electrode; 
   wherein the shock absorber comprises a polymer material having a Shore A hardness value between 20 and 75, and the shock absorber is between 0.25 millimeters and 1.0 millimeters thick.   
     
     
         2 . The catheter of  claim 1 , wherein the polymer material is a thermoplastic polyurethane. 
     
     
         3 . The catheter of  claim 1 , wherein the polymer material has a Shore A hardness value no less than 50. 
     
     
         4 . The catheter of  claim 1 , further comprising an enclosure that at least partially surrounds the at least one shock wave emitter assembly, wherein shock waves are transmitted through a wall of the enclosure. 
     
     
         5 . The catheter of  claim 4 , wherein the enclosure comprises a balloon. 
     
     
         6 . The catheter of  claim 1 , wherein the polymer material is an electrically insulating material. 
     
     
         7 . The catheter of  claim 1 , wherein the at least one shock wave emitter assembly is electrically connected to a power supply configured to generate a generator voltage no less than 6 kV. 
     
     
         8 . A catheter system for treating lesions in a body lumen, the system comprising:
 a catheter comprising:
 an elongate member; 
 at least one shock wave emitter assembly mounted over a distal portion of the elongate member, the at least one shock wave emitter assembly comprising:
 an inner electrode; 
 a shock absorber at least partially surrounding the inner electrode and having a shock absorber aperture aligned with the inner electrode, wherein the shock absorber comprises a polymer material having a Shore A hardness value between 20 and 75, the shock absorber is between 0.25 millimeters and 1.0 millimeters thick; and 
 a conductive band comprising an outer electrode that is aligned with the shock absorber aperture, the inner electrode and the outer electrode forming an electrode pair; and 
 
   a power supply electrically connected to the at least one shock wave emitter assembly and configured to supply a voltage no less than 10 kV to the at least one shock wave emitter assembly.   
     
     
         9 . The catheter system of  claim 8 , wherein the shock absorber comprises a thermoplastic polyurethane. 
     
     
         10 . The catheter system of  claim 8 , wherein the polymer material has a Shore A hardness value no less than 50. 
     
     
         11 . The catheter system of  claim 8 , wherein the polymer material is an electrically insulating polymer material. 
     
     
         12 . The catheter system of  claim 8 , further comprising an enclosure that at least partially surrounds the at least one shock wave emitter assembly, wherein shock waves are transmitted through a wall of the enclosure. 
     
     
         13 . The catheter system of  claim 12 , wherein the enclosure comprises a balloon. 
     
     
         14 . A catheter for treating lesions in a body lumen, the catheter comprising:
 an elongate member;   at least one shock wave emitter assembly located at a distal portion of the elongate member, the at least one shock wave emitter assembly comprising:
 an electrode pair comprising:
 a first electrode electrically connected to a high voltage power source configured to supply a voltage no less than 10 kV to the electrode pair; and 
 a second electrode spaced apart from the first electrode and electrically connected to the high voltage power source, the at least one shock wave emitter assembly configured to generate a shock wave when a voltage is applied across the electrode pair; and 
 
 a shock absorber at least partially located between the first electrode and the second electrode, 
   wherein:
 the shock absorber comprises a polymer material having a Shore A hardness value between 20 and 75 and is between 0.25 millimeters and 1.0 millimeters thick, and 
 the first electrode comprises an edge of a conductive sheath, wherein an overall length of the shock absorber is no less than 3.0 millimeters and an overall length of the conductive sheath is no more than 2.0 millimeters. 
   
     
     
         15 . A catheter for treating lesions in a body lumen, the catheter comprising:
 an elongate member;   a plurality of axially aligned shock wave emitter assemblies located at a distal portion of the elongate member, each of the plurality of shock wave emitter assemblies comprising:
 an electrode pair comprising:
 a first electrode electrically connected to a high voltage power source configured to supply a voltage no less than 10 kV to the electrode pair; and 
 a second electrode spaced apart from the first electrode and electrically connected to the high voltage power source, the plurality of shock wave emitter assemblies configured to generate a shock wave when a voltage is applied across the electrode pair; and 
 
 a shock absorber at least partially located between the first electrode and the second electrode, 
   wherein:
 the shock absorber comprises a polymer material having a Shore A hardness value between 20 and 75 and the shock absorber is between 0.25 millimeters and 1.0 millimeters thick.